Cook the chicken by boiling, baking, or using leftover rotisserie chicken. If boiling, place chicken breasts in a pot of water, bring to a boil, then reduce heat and simmer for about 15-20 minutes, or until cooked through. Shred the chicken once it's cool enough to handle. If baking, drizzle chicken with olive oil, season with salt and pepper, and bake at 375°F (190°C) for 20-25 minutes.

Cook the spaghetti according to package directions until al dente. Drain well.

Dice the green bell pepper and onion.

Shred the cheddar cheese.

Heat the olive oil in a large skillet over medium heat.

Add the diced green bell pepper and onion. Sauté until softened, about 5-7 minutes.

In a large bowl, combine the softened cream cheese, cream of chicken soup, cream of mushroom soup, diced tomatoes and green chilies (Rotel), sautéed vegetables, garlic powder, and paprika.

Mix well until everything is smooth and creamy. If the mixture seems too thick, add a little milk or chicken broth to reach your desired consistency.

Add the cooked and drained spaghetti to the bowl with the sauce mixture.

Add the shredded chicken and 1 cup of the shredded cheddar cheese.

Gently toss everything together until well combined. Make sure the spaghetti is evenly coated with the sauce.

Preheat your oven to 350°F (175°C).

Grease a 9x13 inch baking dish.

Pour the spaghetti mixture into the prepared baking dish.

Sprinkle the remaining 1 cup of shredded cheddar cheese evenly over the top.

Bake for 20-25 minutes, or until the cheese is melted and bubbly, and the casserole is heated through.